Inclusions of native metals and other minerals in diamond from Kimberlite pipe 50, Liaoning, China

Inclusions in diamond from kimberlite Pipe 50, Liaoning Province, China, were detected using a complex of methods of analytical electron microscopy. A close examination of these inclusions revealed the following sequence in the crystallization of their phases. Syngenetic inclusions of native metals (alpha-Fe, native Cr, and a metallic Cr-Fe-Ni phase), sulfides, and, possibly, apatite, graphite, and droplets of magnetite compose the oldest assemblage, which provides information on the high-temperature and high-pressure environment, Florencite and Ce-fluorite affiliate with a younger assemblage of epigenetic minerals. The flaky magnetite and wuestite formed by the postcrystallization oxidation of the native iron.